1. Field of the Invention
The present invention relates to a surgical tool and, more particularly, to a surgical infusion tool having means for diffusing a fluid emanating from the tool.
2. Description of the Prior Art
Ophthalmologists use a wide variety of surgical tools to perform the different types of procedures associated with each individual medical condition of the eye. In a large number of procedures, including vitrectomy and retinal detachment surgery, it is often necessary to infuse a fluid, such as air, perfluoropropane (C3F8), or saline, into the vitreous cavity of the eye.
It is known in the art to infuse such fluid through a cannula which is inserted through a surgical incision and into the vitreous cavity of the eye. An irrigating solution such as a saline solution, or a gas such as air, is thereafter injected through the cannula into the vitreous cavity. In these prior art procedures, however, the cannula is provided with a single outlet. The drawback associated with such prior art cannulas is that the pressure, force and mass flux of the fluid exiting the cannula is concentrated by the relatively large single port. The pressure, force and mass flux exerted by the fluid exiting the cannula may cause damage to the retina or other sensitive portions of the inner eye.
It is also known in the art, as described in U.S. Pat. No. 5,547,473, issued to Peyman, to provide a multi-port tube which surrounds a vitrectomy probe. The drawback associated with this type of prior art device is the difficulty of infusing liquid, such as a saline solution, through the necessarily small ports of the device. An additional drawback associated with such a device is the relatively large diameter of the device in relationship to the relatively small amount of fluid capable of being infused through the small exterior gas delivery channel secured to the exterior of the vitrectomy cutter. This arrangement requires an incision much larger than the diameter of the fluid delivery tube. Accordingly, this type of device requires a very large incision to deliver a moderate amount of fluid to the eye.
The difficulties encountered hereinabove are sought to be eliminated by the present invention.
The present invention comprises a surgical tool for injecting a fluid into a patient. The tool is provided with a housing having a sidewall defining a longitudinal bore having a central axis. The sidewall is provided with an aperture and means are coupled to the housing for forcing the fluid through the central axis of the housing and out of the aperture. A flow diffuser is coupled to the housing and positioned over the aperture.
In the preferred embodiment, the diffuser comprises means for separating the aperture into a plurality of openings to diffuse fluid as it exits the aperture. The flow diffuser can separate the aperture into two or more openings, or may be a cone positioned over the aperture to divert the flow of fluid over the perimeter of the opening.